Controversial plans to disband the South West's dedicated teams of customs officers will be discussed by MPs in the House of Commons.
Customs will rely more on intelligence gathering
The Cornish MP Candy Atherton has secured an adjournment debate on the issue on Tuesday.
Under the proposals, Plymouth's 44 officers will become part of a mobile team that could be redeployed as far afield as Gatwick.
The member for Falmouth and Camborne says the changes are a green light to smugglers.
She says officers will spend up to two days a week travelling and are warning of a rise in smuggling in the region.
Customs and Excise says the current service is static and predictable.
It claims criminals know where and when to commit serious offences and says the officers currently based in Plymouth and Falmouth have failed to detect any class A drugs, substantial amounts of illicit cigarettes or crime-related cash in the last two years.
Customs and Excise plans to use more intelligence to find criminals bringing large amounts of smuggled goods into the region.
Graham Hooker, regional detection manager in the south of England, said: "Officers will be able to respond anywhere.
"So it's wrong to say that the South West will be left without any cover."
Mobile teams being piloted in the region had made seizures outside the South West which had been destined for the region.
A recent seizure in Northampton of 150 kilos of Class A drugs had been destined for people in the Torbay area.
Mr Hooker said: "Our challenge has been to build a modern customs service to match well-financed 21st century criminals.
"This means not only working in new ways but also developing new skills and investing in the latest technology, and there will be a better service as a result."